Dispersion of Student Achievement and Classroom Composition

Abstract

This chapter reviews existing findings on the effects of student achievement variability at different levels of the learning environment: within classrooms and schools, between schools, between tracks, as well as across educational systems of different countries. In addition, it summarizes findings on classroom composition effects on achievement as well as motivational and psychosocial outcomes of students. The review focuses on achievement composition in terms of achievement level and dispersion. Beginning with a brief summary of theories on the learning environment and emerging effects of school and classroom composition more generally, the chapter shortly depicts approaches to operationalize student composition. The main part, then, (a) reviews existing findings on student achievement variability at different levels of the learning environment. In addition, it (b) summarizes findings on the effects of classroom and school composition on individual student outcomes. The main dependent variable of these studies is individual student achievement, especially in mathematics and reading comprehension. In addition, the review includes studies examining effects on further student outcomes, such as motivation and psychosocial characteristics, for example, academic self-concept. It also aims at including studies investigating if composition effects are comparable in size between high and low achievers. The chapter concludes with a discussion of the limitations of studies on composition effects and points out knowledge gaps for future research. It also relates its topic of composition to the overall perspective of International Large-Scale Assessments as well as to the cross-cutting theme of the section—equity and diversity.